A plant-geographical study of the genusDorycnium MILL. (Fabaceae) in the Czech Republic

Two species of the genusDorycnium with the most northern distribution reach the absolute northern limit of their distribution areas in the Czech Republic.Dorycnium germanicum, a less ecologically plastic and more xerothermic species, covers a compact area in south Moravia, connected with its occurrence in Lower Austria.Dorycnium herbaceum, and ecologically more tolerant species, has its primary distribution area in south-east Moravia; this is connected with the Slovak part of the area of this species; secondary occurrences are scattered throughout other parts of Moravia and Bohemia. The distribution of both species was evaluated, using 23 herbarium collections. Climatic characteristics are provided for 54 climatic and ombrometric stations from the distribution area of both species. In the Czech RepublicD. germanicum represents the Illyrian-Noric migration element whileD. herbaceum represents the Carpathian one. There is a clear climatic differentiation between the localities of both species:D. germanicum occurs in dryer and warmer regions thanD. herbaceum. An introgression, zone was identified in the vicinity of the twon of Uherské Hardi?tě and the area south-east of this town. This zone coincides with the area where most of the identification problems with these species occurred.